While you wait for answers, we may have found some information which could help you.
Success
Message
Bleed a boiler?
Fan Cage Making noise on a Riello 40 FS?
Bleeding it after oil ran out?
can you fix the pump on a riello40?
How to increase air supply to Riello RDB Burner?
My Riello 40 loses it prime ?
Burner not working ?
how can i mend my riello burner rdb1 483t50?
Riello 40 Burner problem?
My riello burner lights for about 12sec and then locks out?
riello 40 starts, runs fine then stops. ?
Oil not reaching burner?